March 2019

Research highlightKeeping NSAIDs part of the femtosecond phaco picture

by Maxine Lipner EyeWorld Senior Contributing Writer

Small pupil in a diabetic patient, at higher risk for CME

Patient with pupillary miosis induced by femtosecond laser pretreatment of the lens during cataract surgery

A mature cataract may require more energy for removal, placing the patient at higher risk for postoperative inflammation, including CME.
Source (all): Kendall Donaldson, MD

Considering their role in forestalling prostaglandin release

Can use of an NSAID help curtail prostaglandin release in patients undergoing femtosecond laser capsulotomy during cataract surgery? A study1 in the Journal of Ophthalmology indicated that the amount of prostaglandin in the aqueous humor was significantly lower in the eyes that received an NSAID, according to Kendall Donaldson, MD, professor of ophthalmology, Bascom Palmer Eye Institute, Plantation, Florida.
“We broke it down just looking at this one component of the procedure,” Dr. Donaldson said, adding that the other femtosecond-related aspects of the procedure are so variable with regard to the amount of energy used. They wanted to look at the part of that procedure that varies less by surgeon style.

Monitoring prostaglandin levels

Investigators were inspired to take a closer look at prostaglandin levels after noticing that cataract procedures with the femtosecond laser seemed to be characterized by a decrease in pupil size compared to traditional cataract surgery, Dr. Donaldson said. “Also, there had been two studies2,3 that had shown differences in prostaglandin levels,” she said. “We wanted to confirm that and also look at our patients because we were noticing that the pupils were going down substantially.” Researchers also investigated the degree of pupillary miosis across various laser platforms in earlier studies.
Twenty patients were included in the study with the femtosecond laser only being used for the capsulotomy creation. Of the 20 patients, 10 had pretreatment four times a day with the nonsteroidal generic ketorolac 3 days preoperatively, Dr. Donaldson said.
Investigators observed pupillary miosis in most patients undergoing femtosecond cataract surgery. “The miosis was more pronounced in the patients who did not have pretreatment with a nonsteroidal,” Dr. Donaldson said. “Also, the levels of prostaglandins were much lower in the patients who were pretreated.” This was consistent with the literature, where it has been established that pretreatment with a nonsteroidal before cataract surgery can help give a more dilated pupil.
Omidria (Omeros, Seattle), which includes the NSAID ketorolac as well as phenylephrine, is FDA approved for use during cataract surgery, and could be included in future studies as researchers try to prevent miosis in patients receiving femtosecond laser treatments, Dr. Donaldson said.
“We’re trying to figure out how to avoid miosis because it can increase the risks of cataract surgery,” Dr. Donaldson said, explaining that physicians want to avoid introducing a new complication with femtosecond technology, which could offer safety benefits. To avoid a potential downside, investigators are trying to find better ways to prepare these patients, she said.
“I think we have to have a way to keep the pupils dilated for femtosecond cataract surgery, whether it be pretreatment or something like Omidria during cataract surgery,” Dr. Donaldson said. “We have to find a way to reduce the prostaglandin release so we don’t get that pupillary miosis. Our goal is to make the surgery as safe as possible.”

Clinical implications

When performing cataract surgery, Dr. Donaldson typically uses Ilevro (nepafenac, Novartis, Basel, Switzerland), prescribing the once-a-day agent for 3 days prior. In cases where insurance doesn’t allow for a brand-name product, she prescribes generic ketorolac, which must be administered four times a day and can dry the eye, she noted. “We would like to use Omidria, however, it has been difficult because we’re a hospital-based academic practice and there are some financial issues involved in bringing this into a hospital setting. However, we’re working to overcome these barriers,” Dr. Donaldson said. “But I think in an ambulatory surgical setting, I would be using Omidria during my cases.”
While the trend around the country has been to use less drops both before and after cataract surgery, Dr. Donaldson thinks NSAIDs still very much have a role. “It has been shown that preoperative topical antibiotics are not helpful, but I think we need to maintain the preoperative treatment with nonsteroidals even if we stop the pretreatment with antibiotics,” she said. “I think there still are many good reasons to use nonsteroidals, including the pupillary issues, the potential prevention of CME, and the pain-relieving aspect of it.”
Practitioners need to be especially diligent with femtosecond patients for several reasons, Dr. Donaldson continued. First, their expectations are higher. Second, there is the effect of the femtosecond laser that causes the pupils to decrease in size. “This could potentially be changing the risk profile of surgery in the patients with the highest expectations,” she said. “Of course, we want the best outcomes for everyone, but achieving it in this group of patients is especially crucial.”